This invention relates generally to encoded sheet material, and more particularly to methods for managing encoded sheet material having information recorded thereon.
Despite the publicity about the paperless office, paper remains an important media in today""s working environment. Many efforts have been made to integrate paper documents with computer-based information systems. These efforts generally involve two scenarios. The first scenario involves scanning an existing physical document to create a digital copy, assigning a digital file name and then managing the digital copy as any other digital file. The second scenario involves creation of a physical document from an existing digital document or file such as by printing. To aid in the integration process, a barcode or a Dataglyph may be printed or otherwise attached to a physical document. Dataglyphs are generally less visually disruptive than barcodes. Both barcodes and Dataglyphs provide a means for the computer to grasp intentionally printed information on the paper document. Since both are generally applied at the time the information is recorded on the sheet of paper (but may be applied later through the use of an adhesive label), both generally appear on the same face of the sheet of paper as the recorded information.
At the organization level, many documents, such as contracts, reports, files, technical documentation, etc., have to be physically stored for legal, administrative or operational reasons. Attention must be paid to their indexing and classification in order to keep document retrieval cost at an acceptable level. One solution is to physically attach a barcode or Dataglyph to an existing paper document and scan the document into the computer-based information system.
Having a record of a paper document in a computer-based information system does not solve the problem of knowing where the actual paper document is located. Even if location information is stored at the time the paper document is input into the system (such as when the barcode or Dataglyph is read by the computer-based information system), the paper document may have been moved when a user retrieved it and later replaced it.
Most paper documents in offices do not contain barcodes or Dataglyphs and are not part of a computer-based information system. Most offices have piles of document on shelves, desks and the like that are classified in an ad-hoc and personal manner. Finding a document in one of these ad hoc filing systems often means browsing through several piles to find a particular document.
The verification that a paper or hard copy version of a document is an original, as opposed to a copy or imitation, is important in many businesses and legal transactions. Examples include contracts, stock certificates, bank notes, premium bonds, etc. Verification of authenticity of an original document has become harder to perform since modem techniques enable the production of high quality copies which are frequently difficult to detect from the original. Even if an original paper document included a barcode or Dataglyph on the face of the document, any copy of the paper document will also include the same barcode or Dataglyph.
Much work has been done in order to verify the integrity of the content of a hardcopy document as well as its origin (this is referred to as authenticating a document). Verifying the content and origin (authenticating) of a hard-copy document consists of making sure that its content was not tampered with, and that it really originates from the supposed source. This prevents manipulation of the content of a document, while true (i.e. not manipulated) copies remain possible. Originality check is concerned with discriminating copies from the original hardcopy document. The problem of originality is closely related to the problem of authentication because in most cases where originality is important, the content is also important. However, in some cases the originality of a sheet of paper itself is important, independently of its content. Consider for instance the case of a sheet of paper being circulated to collect signatures for a petition. When it comes back, the originator expects to have the original sheet (and not a possibly manipulated copy).
The use of edge marking of sheet materials has been proposed for various applications. U.S. Pat. No. 5,085,417 to Copham, Method of Encoding Stacks of Printed Materials, describes a process for using edge markings to identify one customer""s order for form checks from another customer""s. During manufacture of a sheet of checks, a coded image is provided at the cutting boundaries of the stock sheets, so that when the checks are cut from the stock, an identification code appears on the checks when viewed from the edge. The edge-visible code is obtained by cutting the paper precisely where marks are located. A different code is provided for each customer to enable workers to look at the stacked check books at the edge to determine if another customer""s checks were erroneously placed.
U.S. patent application Ser. No. 09/222,920 filed Dec. 30, 1998, Encoded Sheet Material and Sheet Processing Apparatus Using Encoded Sheet Material, which is assigned to the same assignee as this application, describes pre-marking of edges of paper reams/stacks (during manufacture) with information related to the paper""s physical properties (e.g. its weight, color). This encoded information is read and used by printers (and other recording devices which record information on the faces of the sheet material) when selecting paper from paper trays.
An encoded sheet material, according to the invention, includes a sheet of material having a first surface, a second surface disposed opposite the first surface and an edge extending between the first surface and the second surface and peripherally about the sheet of material, the edge having indicia arranged thereon to form a code uniquely identifying the sheet of material. A system for managing an encoded sheet of material includes a code reader operative in conjunction with an encoded sheet of material for reading an edge code; wherein the encoded sheet of material has a first surface, a second surface disposed opposite the first surface and an edge extending between the first surface and the second surface and peripherally about the sheet of material, the edge having indicia arranged thereon to form a code uniquely identifying the sheet of material; a sheet processing apparatus for reading information from and/or writing information to at least one of the first and second surfaces of the encoded sheet material; and a processor in communication with the code reader and the sheet processing apparatus for associating the information with the edge code.
By providing each sheet of material with a unique edge identifier, any information that may be recorded on the sheet of material may be associated with that sheet of material. By placing the unique identifier on the edge, both surfaces are available for recording information. The edge marking can be made with a visible or an invisible ink. If the recording device includes an edge reader coupled to a processor with a memory, whenever a user makes a copy of an electronic file, the recording device reads the edge marking on each sheet of material used, and the processor associates that sheet of material with the electronic file. This association can be stored in memory. This feature is useful for tracking or monitoring physical copies of an electronic file. Additional information or metadata may also be associated with the electronic file.
The association information may be stored and used for other purposes, such as monitoring the number of copies made of a particular file, for monitoring the location of the copies and for monitoring the number of sheets of material used. The association information can be made or updated at any time. For example, if an electronic file is printed on a sheet of material with a unique edge marking, that association may be made and stored in a memory at the time of printing or later. If that recorded sheet of material is used to make a photocopy, an edge reader in the copier can make an association of the read edge marking of the xe2x80x9coriginal hard copyxe2x80x9d with the edge marking of the sheet of material used to make the photocopy. This information may be stored in memory and can be used to update the association information with the original electronic file and create a new association for the xe2x80x9coriginal hard copy.xe2x80x9d
Retrieving information associated with a sheet is accomplished by reading its edge identifier and querying the infrastructure to retrieve this information, given the identifier. Preferably, sheets of material are pre-marked at production time. If pre-marked at production time, each sheet can be given a code identifying the ream to which it belongs as well as uniquely identifying that sheet. The code can include a portion identifying the ream, manufacturer, and other information that a user might require. Some reams of sheet material may be specially coded with special visible and/or invisible inks and used as special bond paper for financial instruments, for example. Indeed, some organizations may wish to reserve special reams of material.
Edge-readers can either be embedded in the recording devices (such as printers, facsimile machines, photocopiers, shredders, etc.) or affixed in work places (e.g. desktops). The edge readers are coupled to a computer or network where the read association information may be read and/or written. The edge readers enable the automatic association of printed-sheet  less than - greater than  document. Users may also use any sheet of a document either to obtain related service by passing the sheet through an edge-reader, or to establish an association in a similar way.
Documents in paper form are largely used in almost all businesses. Documents are frequently stored in an ad-hoc manner (e.g., on personal shelves in an office) or formally (e.g., legal or contractual documents are stored in filing cabinets, etc. in banks, administration offices, etc.). Document classification and retrieval is often problematic and costly. The method of the invention provides computer support to these two tasks, without disrupting the user""s normal work practice, and requires less effort. The invention enables documents to be automatically indexed in place (i.e., in their normal storage area) and retrieved by obtaining storage information from a computer-based system.
The encoded sheet material of the invention may be used to index and manage physical documents. Indexing and managing physical documents generally involves four steps. First, the physical documents must be indexed, which often includes generating some form of unique identifier. Then the physical documents must be inserted in the storage area, i.e., in accordance with some classification scheme. Retrieving the stored physical document involves searching through the storage area using the classification scheme. Finally, after use, the document must be re-inserted into the storage area, which location may be different from the original location.
Physical documents may be edge marked and the edge markings used to index and retrieve them from their storage locations. A method of managing a physical document, wherein the physical document includes at least one sheet of material, includes marking an edge of the at least one sheet of material with indicia arranged to form a code identifying the sheet of material, storing the physical document in a storage location, indexing the physical document by associating the code with the storage location, and storing the indexing information in a computer-based information retrieval system. A method of retrieving a physical document stored in a storage location, includes obtaining a code associated with the physical document, wherein the physical document includes at least one sheet of material having a first surface, a second surface disposed opposite the first surface and an edge extending between the first surface and the second surface and peripherally about the sheet of material, the edge having indicia arranged thereon to form the code identifying the sheet of material, and information recorded on at least one of the first and second surfaces of at least one of the sheets of material, using a scanning device to scan the storage location for the code, and when the output of the scanning device indicates the location of the sheet of material having code, retrieving the physical document.
The invention provides a computer-implemented system for the indexing, storage and retrieval of paper document from piles, filing cabinet, shelves and more generally from document storage areas where document edges are visible. By using a robust code, such as a large barcode on the edge of the documents, which is visible (to the particular scanning device) on the edge of the documents, physical documents may be input into a computer-based system and located for retrieval. In addition to storing the edge codes and location information, images of the storage area (shelves, piles, etc.) may also be stored in the computer-based system. Documents can be located by scanning the storage location for the document""s edge code or by accessing the computer-based system and retrieving the storage location.
Since each sheet of paper holds a unique identifier (preferably) pre-marked on its edge at production time, indexing is automatic; the pre-marked edge codes constitute the minimal required index. However, this does not preclude the use of other forms of indexing, in addition. Since the physical documents can be easily retrieved (by scanning stacks of files for their edge codes), storage of physical documents becomes as simple as stacking documents as they arrive. However, any other classification scheme can also be used. Documents must be stacked so that the edge codes can be read. Physical document retrieval is computer or network supported; the computer or network indicates via an output device where the document is located. For example, the computer may display an image of the storage area where the document is located. Re-insertion of a physical document is equally simple.
An original document is one from which a copy, reproduction or translation is made. In the case of a contract, the original contract is the one (or ones in the case of duplicate originals) with the original signatures affixed to it. Originality goes to a document""s content as well as physical integrity (i.e., the particular sheets of paper used). Authenticity of a document goes to the integrity of the information, i.e., whether the information conforms to the information in the original. An authorized copy of an original document is authentic if it conforms to the original so as to reproduce essential features. The invention enables the authentication of originals as well as copies. The invention provides a method of authenticating the sheets of paper (material) on which documents are recorded as well as authenticating the information on the sheets of material.
A method of creating an authenticatable sheet of material, according to the invention, includes measuring at least one physical property of the sheet of material; marking an edge of the sheet of material with indicia arranged to form a unique code identifying the sheet of material, wherein the sheet of material includes a first surface, a second surface disposed opposite the first surface and an edge extending between the first surface and the second surface and peripherally about the sheet of material; and recording the measured physical property in a measure database indexed by the edge code. To verify the validity or authenticity of a sheet of material, the edge code is read, the same physical property is measured and the measured value is compared with the previously stored value extracted from the measure database. If the two are substantially equal, the sheet of material is authentic.
The use of edge codes and physical property measures can be used to authenticate a document, i.e., a sheet of material on which information has been recorded, and verify its originality. A method of creating an authenticatable physical document which includes information recorded on a surface of the sheet of paper includes using the edge code with the information to generate an encryption hash, digitally signing the encryption hash and recording the digitally signed encryption hash on a surface of the sheet of material. If a physical property has been measured and indexed in a measure database, the originality of the sheet of material can be verified as well. A digital signature does not hide the content of the information, but is used primarily to guarantee the identification of the sender of the information and its integrity. For added security, the encryption hash may be encrypted rather than just digitally signed.
Verifying the authenticity of a sheet of material involves reading the digitally signed hash on the document, decrypting it, generating a new hash from the edge code and a portion of the information. The two encryption hashes are then compared. If they are equal, the document is authentic. Additionally, the edge code can be used to determine if the sheet of material is original, by measuring the physical property and comparing its value to the value stored in the measure database.